Making use of foodstuffs that are usually discarded before or during prep is becoming common practice in commercial kitchens, as chefs focus on innovative ways to cut waste. So it comes as little surprise that whey – a byproduct of cheese-making – is finding its way onto more menus.

In its basic form, whey is the liquid left after milk has been curdled and strained to make cheese. It can be turned into soft whey cheeses, such as ricotta, or added to baked products to perform an array of functions, from emulsification to flavour enhancement.

While whey is used regularly in food manufacturing, it could be described as a Z list star in this arena, noted simply on the list of ingredients. However, in restaurants whey is rapidly heading towards A list status, as the number of establishments highlighting it as dish component steadily grow.

As chef Richard Mann, who has just moved from The Camellia in West Sussex to The Little Fish Market in Hove, says, whey has “plenty of flavour and is rich in protein,” making it a versatile addition to sauces, stocks and bread.

At Silo in Brighton, whey “almost never leaves the menu,” according to founder and chef Douglas McMaster, who recently served whey with potatoes and blackberries.

“When we receive food it's whole,” he explains. “Whey is always in the menu because it's in milk and we always have milk. It's not a case of choosing to put it on the menu because we fancy it, it's because it's there. We won't waste it.”

The trailblazers

Richard Mann, former head chef at The Camellia at South Lodge, West Sussex, uses whey in a starter of homemade goat milk ricotta, asparagus, strawberry, toasted almonds and caramelised whey: “Whilst researching ricotta making, I came across a caramelised whey ‘cheese,’ which is very popular in Scandinavia. Caramelised whey is basically the sweet whey left over from cheese making that is reduced down over a period of time until it changes colour and thickens, at which point cream or milk is added. It ends up texturally like caramel but with quite a unique flavour profile. To make the dish, we made our ricotta and used some of that whey to poach the asparagus, which gave it another level of flavour. I made a strawberry liqueur puree as well, to add some sharpness, and sliced some fresh strawberries at the last minute. For texture, I made a rye crispbread, also influenced by the Scandinavian diet. The dish was finished with toasted almonds, some fresh pea shoots and a few tiny balls of the caramelised whey. With the whey being caramelised, it adds both a rich sweetness and savouriness to the dish. It also provides some texture, as it's firm compared to the ricotta, which is beautifully soft and slightly acidic from the lemon juice.”

Douglas McMaster, founder and chef at Silo in Brighton, describes a smoked shiitake mushroom dish with rosehip and whey reduction that he created for a dinner held in collaboration with Ernst restaurant in Berlin: “We visited a farm outside of Berlin where we milked the cows and made yoghurt from the milk. I took the whey from the yoghurt and reduced it down. We'd foraged for rosehips on the same farm, so I cooked them down, took the seeds out, then kept cooking them down until they produced a sort of paste. I carried on reducing the whey until it turned a slight golden colour and then swirled it through the rosehip paste to produce a jam-like texture. We took some shiitake mushrooms that had just been harvested and cooked them over oak on the yakitori grill, before putting them in a dashi-style stock and serving them on top of the rosehip and whey reduction. Reducing the whey helps intensify the acidity, but you also get this intense caramelisation due to the protein cooking down, so it's uniquely sour, rich and naturally sweet at the same time. Because it's naturally sweet, you need something that will push it in a savoury direction which is what the shiitake mushrooms do. You have the naturally bright and sweet rosehip and whey with the umami, salty and savoury mushrooms. The balance is perfect.”

Mark Jarvis, chef-owner of Anglo, Neo Bistro and Stem restaurants in London, serves a starter of whey with English peas, black garlic emulsion and salted egg yolk at Anglo: “To make the starter, first we put the garlic puree and egg yolk puree in a bowl. We then heat the peas in a herb stock to add flavour before putting the peas on top of the purees. Finally, we place the whey sauce over everything. Whey provides acidity and gives the dish a nice roundness. It works really well as it's subtle and not overpowering. It doesn't just work for sauces, it can be cooked or fermented too.”